This project will investigate the economic and demographic determinants of three recent changes in the American housing market: (1) the increase in the number of primary individuals and childless couples who purchase single family homes, (2) the increase in the number of apartments converted into condominiums, and (3) the increase in the number of single family homes undergoing subdivision. The research will focus on the combined effects of declining household size and increasing house size on the three changes in housing tenure. To analyze these processes, the investigator will utilize data on individual housing units and their occupants from Annual Housing Surveys for the period 1974 to 1978.